Multi-stage compressor



Dec. 2, 1958 M. M. KADISON MULTI-STAGE COMPRESSOR 5 Sheets-Sheet 1 I Filed April 4, 1955 EN a 4 $2. C? 3 w/ m MS. 7. Ev 5 a h QQN -I H, J f 1 k l nu b wx II V MW 7 H uIIOI W WIIQIWW NW In Hid/44 a v v w V QM M Q m up 0% 1 3 .Ir fi $3M 5 5 8 3+ Ev Q u Q E N ww m m No v E 3% g Q m INVENTOR.

MILTON M. KAD/SO/Y I ATTORNEY Dec. 2, 1958 M. M. KADISON 2,862,656

MULTI-STAGE COMPRESSOR- Filed April 4, 1955 5 Sheets-Sheet 2 INVENTOR.

\ Q! MILTON M. mw/so/v 2, 1958 M. M. KADISONQ MULTI-STAGE COMPRESSOR 5 Shee ts Sheet 3 Filed April '4, 1955 r FLJFL PiD..

IN V EN TOR.

M H m M. m. N T .3 m W 5 Sheets-Sheet 4 Filed April 4, 1955 INVENTOR.

MILTON M. KAOISO/V N BY ,{TTOKIYEY Tnited States 3 MULTi-STAGE COMPRESSOR Milton M. Kadison, Cremat on-Hudson, N. Y., assignor of twenty-five percent to Anna Colton, Bronx, N. Y., twenty-five percent to Hyman Bettigoie, New York, N. Y., and fifty percent to Reba David, Bronx, N. Y.

Application Aprii 4, 1955, Serial No. 499,099

2 Claims. or. 230-202 pressor, and will be described hereinafter with particular reference thereto, it is appreciated that the invention may also serve as a fluid pump or compressor, and with slight modification as a fluid motor; and hence, the term compressor as used hereinafter is intended to comprehend the various uses for which the invention may be employed.

The particular embodiment of the pre'sentinv'ention which is illustrated in the drawings and which will be described hereinafter in greater detail comprises generally a housing provided with a pair of spaced cylinders, a pair of pistons slidable in the cylinders, fluid conduit means connecting the pistons together for movement as a unit and serving to transfer fluid between the cylinders.

Heretofore, the use of compressors, as in the common hermetic design of refrigerating rriotoncomtaressors, required special motor windings, and extreme care in assembly and shipment to avoid dirty contamination of the refrigerant path. That is, in order to cool the motor, it was necessary to suck the refrigerant through the motor windings, which operation served to sharply increase the work of compression. Further, in prior refrigerator motor-compressor constructions, it was impossibleto repair or replace the motor without breaking into therefrigerant system, and hence no switch contacts or commutators could be placed inside the motor housing. This seriously limited the types of motors and controls capable of being employed, and prevented the use ofhighly desirable centrifugal switches and commutator type motors. in addition, the refrigerant was in intimate contact with the crankcase oil, presenting the constant danger "of refrigerant contamination and the plugging or breaka e of elements in the refrigerant system.

Accordingly, it is a general object of the present invention to provide a novel compressor construction which retains the advantageous features of the prior compressor art, and overcomes the above-mentioned difliculties. Some of the prior art advantages retained in the instant construction are those of life-time bean'nglubrication, direct motor-compressor coupling, two bearing motorcompressor mounting, silent operation, and the use of a shaftless motor built into the unit. A I a It is another object of the present invention to provide a compressor of the type described whicliis extremely compact in construction and eflici'ent in operation, so as to require a minimum of space and permit the use of less powerful, relatively small driving means or motors to achieve the same refrigerating capacity as previous c o'mpressors. Specifically, for equal refrigerating tonn' ge, the compressor construction of the present invention requires 25 perce'nt less horsepower, up to '80gpercent less overall size or volume, and has effected up to 30 percent reduction in weight.

atent ice It is another object of the present invention to provide a compressor having the advantageous characteristics mentioned above and which is adapted for use with conventional or stock types of motors without the need for special handling. This, of course, reduces costs and facilitates motor repairs and replacements in the field. Moreover, the motor can be readily removed and replaced in the "field, without adversely affecting the lifetime lubricating system or refrigerant. In addition, the construction of the present invention permits of quick and easy disassembly and reassembly by mechanics of only ordinary skill, insuring correct reassembly and efficient compressor operation independent of the me'chanics skill.

It is still another object of the present invention to provide a fluid compressor of the type described which includes novel means for separating dispersed particles or dispersoid from the compressed fluid, to prevent the entrance of water, oil or other foreign material into the refrigerating circuit. The dispersoid separator of the present invention is adapted to be located in the high pressure side of the compressor, occupying a relatively small space therein, and eliminates the need for a bulky, full-flow separator in the refrigerant circuit. While the highly improved separator of the instant invention is capable of effective operation over long periods of time, rapid replacement, as for cleaning, may be easily accomplished without loss of refrigerant.

it is a further object of the present invention to provide a compressor construction having the improvements mentioned in the foregoing paragraphs, and wherein all shaking forces and rocking couples in the vertical plane are eliminated by a novel construction employing counterweights which also effect positive feeding of lubricant to all bearing surfaces. While the motor coils and refrigerant circuit are both completely isolated from the lubricant, all working parts, including motor bearings, are automatically and positively, flood-splash lubricated at the required rate for all operating speeds.

The compressor construction of the present invention contemplates a further, highly advantageous construction, wherein the fluid passing between the compression stages is effectively cooled by the liquid of the lubricating system, so as to substantially increase overall refrigerating efficiency.

It is still a further object of the present invention to provide a compressor having the advantageous characteristics mentioned in the foregoing paragraphs, which is simple in construction, requiring a minimum of parts, which is durable in use, and which can be manufactured, sold and maintained at a reasonable cost.

Other objects of the present invention will become apparent upon reading the followingspecification and referring to the accompanying drawings, which form a material part of this disclosure.

The invention accordingly consists in the features of construction, combinations of elements, and arrange ments of parts, which will be exemplified in the construction hereinafter described, and of which the scope will be indicated by the appended claims.

In the drawings: 7 V

Fig. l'is a sectional elevational view of a motorcompressor assembly constructed in accordance with the present invention. p v

Fig. 2 is a sectional elevational view taken substantially along the line 2-2 of Fig. 1.

Fig. 3 is a sectional elevational view similar to Fig.2, but with the piston assembly removed from the compressor housing. I

Fig. 4 is a sectional view taken substantially along the line 4-4 of Fig. 3.

Fig. 6 is a sectional view taken substantially along the line 66 of Fig. 2.

Fig. 7 is a rear elevational View showing the separator of the present invention, removed from the assembly and partially broken away for clarity of understanding.

Fig. 8 is a partial front elevational view of the separator.

Fig. 9 is a side view of the separator.

Fig. 10 is a top plan view of the separator of Fig. 7.

Fig. 11 is a bottom plan view of the separator of Fig. 7.

Fig. 12 is a longitudinal sectional view showing a valve member of the device, removed therefrom.

Fig. 13 is an end view of the valve member of Fig. 12.

Fig. 14 is a partial, sectional view taken substantially along the line 1414 of Fig. 3.

Fig. 15 is a partial sectional view taken substantially along the line 15-15 of Fig. 3.

Fig. 16 is a front view showing one rotary counterweight of the device, removed therefrom.

Fig. 17 is a sectional view taken substantially along the line 17-17 of Fig. 16.

Fig. 18 is a rear view showing the counterweight of Fig. 16.

Fig. 19 is a side view, partly broken away, showing the double piston unit of the instant device, removed from the assembly.

Referring now more particularly to the drawings, the embodiment of the invention illustrated therein comprises a housing, generally designated 20, which includes a main or compressor housing section 21 and an auxiliary or motor housing section 22.

The main or compressor housing section includes a generally rectangular, normally horizontal bottom wall 23 formed with a plurality of parallel spaced, internal ribs 24. Extending upwards from opposite sides of the bottom wall 23 are a pair of facing, spaced side walls 26 and 27, which are formed, respectively, with horizontally disposed cylinders 28 and 29. A front housing wall 31 extends upwards from the front side of the bottom wall 23, and extends between the side walls 26 and 27. The upper portion of the front main housing wall 31 curves rearwards and upwards, as at 32, to merge smoothly with a generally dome-shaped top wall 33 which extends between and is fixedly secured to the upper portions of the main housing side walls 26 and 27. The inner or under surface of the top wall 33 is formed with a laterally extending, depending rib or fin 34, while a plurality of parallel spaced, external ribs or fins 36 extend forwards and rearwards on the top and bottom housing walls 33 and 23, and vertically along the front housing wall 31. The compressor housing 21 is preferably integrally cast of aluminum, or other lightweight, high conductivity material, for purposes appearing more fully hereinafter.

The rearward end of the compressor housing 21, to the right in Fig. 3, is open, generally circular in configuration and preferably formed with peripherally extending, shoulders 33 and 39, respectively disposed externally and internally of the compressor housing. The rear end of the compressor housing is further formed with a peripherally extending internal groove 41, disposed between the shoulders 38 and 39 and generally wedgeshaped in section. A plurality of supporting feet or legs 42 project from the corners of the main housing bottom wall 23 for supporting the housing on an appropriate surface, and may be shaped to receive anchoring bolts or other fastening means, as desired.

The front wall 31 of the compressor housing 21 is provided internally with a centrally located, rearwardly extending tubular journal support 43, and a plurality of fins or webs 44 extending radially from the journal support along the front housing wall 31' toward the top and side walls of the main housing section. The front housing wall 31 is further provided on its interior,'just below the journal support 43 with a laterally extending, hollow cylindrical portion or pocket 46 which terminates at the opposite housing side walls 26 and 27 More specifically, the interior hollow or cavity 47 of the pocket 46 is generally cylindrical in shape, and preferably provided with an upwardly facing, longitudinally extending internal groove or trough 48.

Formed in the front wall 31 of the compressor housing 21 is a rearwardly and upwardly inclined through bore 49 which opens intermediate its ends into the interior of the tubular journal support 43. A plug 50 is threadedly, or otherwise inserted into the forward portion of the bore 49 to close the latter and permit communication through the inner bore portion between the interiors of the compressor housing section and the journal support. A generally horizontally disposed bore 52 extends forwardly into the front wall 31 of the compressor housing between the journal support 43 and the cylindrical pocket 46 and communicates with the interior of the latter through a downwardly extending passage 53. Thus, the bore 52 and passage 53 communicate between the interior of the cylindrical body or pocket 46 and the interior of the compressor housing.

A horizontal valve member 54 is disposed slidably within the bore 52, and includes an enlarged apertured head 55 (see Figs. 12 and 13) on one end of a hollow tube 56. Suitable resilient means are provided, such as a helical coil spring 57 disposed within the tube 56 to urge the valve member and head rearward. In addition, a horizontal, blind bore 58 (see Fig. 3), extends forwardly into the front housing wall 31 between the hollow body 46 and journal support 43, on one side of the bore 52; and, a spring pressed wiper finger or pin 59 is slidable in the bore 58 and resiliently urged rearwards into the compressor housing, all for purposes appearing presently.

The upper, curved portion 32 of the front housing wall 31 is formed with an internal boss 61 having a down wardly and rearwardly extending through bore 62, which is normally closed by a threaded plug 63 or other suitable means, and facilitates the introduction and removal of liquid lubricant from the compressor housing interior. An external boss or protuberance 64 is formed on the compressor housing side wall 27 extending from the cylinder 29, to the front wall 31, and is formed with a longitudinal bore 65 for a purpose appearing more fully hereinafter. I

The horizontal cylinders 28 and 29 are in substantial, longitudinal alignment, andare preferably formed with circumferential, external heat dissipating fins 66 and 67. respectively. The cylinders 28 and 29 are preferably formed integrally with the compressor housing 21, having their outer ends open and the inner portion of each cylinder internally, circumferentially recessed for receiving cylinder linings or bushings 68 and 69. More specifically, the inside diameter of the cylinder 28 increases outwardly by steps so as to define outwardly facing, annular shoulders 70 and 71 in alternate relation with circumferential, internal lands 72 and 73. The land 72 is formed with an annular groove 74, and the land 73 is formed with an annular groove 75, both annular grooves being generally wedge-shaped in section.

The inside diameter of the outlet or high pressure cylinder 29, while generally less than that of the low pressure or inlet cylinder 28, also increases outwardly in steps defined by annular, outwardly facing shoulders 79, 8% and 81, and alternate circumferential lands 82. 33 and 84. The lands 82 and 84 are each formed with an annular, internal groove 85 and 86, which are also generally wedge-shaped in cross section. In addition, the relatively small, high pressure cylinder 29 is formedin its lower portion with a longitudinal bore 89 extending inwards from the shoulder and communicating through the 46,.as at 90 inFigS. 3 andS. g

A dumbbell-like piston unit, -g'eiierally"designated' 12,

'extends between the inner portions of the" cylinders 28 and 29 and includes pistons 93 and'94 on its'opposite'ends slidable, respectively, in the bushings or cylinder liners 68 and 69.

Disposed within the circumferential, 'inter'nal la'n'd 72 is a suitable low pressure inlet valve96 having on opposite sides thereof a back-up plate'f97 and inlet'valv'e seat '93, the back-up plate being adjacent to the shoulder 7E and maintained in abutting engagement with the latter by a resilient, G-shapedretaining ring 99 receiv'edfin' the groove 74and resiliently engaging'the valveseatett. A seal ring 101, preferably fabricated of dead-soft alumi- -num or other suitable material, is wedged between the back-up plate 97, land 72 and lo'w 'pressure inlet valve 96.

A porous filter disc 102 is disposed within the land 72 just outwards of the retaining ring 99, and a peripherally stepped cylinder closure or h ad 103 is:positi0ned just outwards of the filter disc,-par tially Within the land 92 and partially within the land 93. That-is, the peripherally stepped cylinder closure or head 1113 is maintained in abutting engagement with the outwardly facing shoulder 71 by a resilient, C-shaped retaining ring 1114 and extends within the land 72 to hold the filter disc in position. The dead-soft seal ring 105 is wedged between inlet cylinder head 103, the'shoulder 71 and land 73, to'prevent the passage of fluid therebetween. A suitable inlet shut-off valve 107 is provided on the cylinder end closure 103, which permits selective communication 'through the cylinder end closure, filter disc 102, and inlet valve 96 with the interior of the low pressure cylinder. The inlet shutoff valve 107 includes appropriate means, as at 1118, for connection to a source of fluid supply. v

Disposed within the circumferential, internal land 82 of the high pressure cylinder 2 9'isa suitable high pressure outlet or discharge valve 111 having a discharge valve seat 112 onits inner side and a discharge valve back-up plate 113 on its outer side, the discharge valve seat being held in abutting engagement with the annular shoulder 79 by a resilient, C shaped retaining ring 114 received in the groove 85 and bearing against the discharge valve back-up plate.

A particle-or dispersoid separator 116 is seated within the circumferential land 83 in engagement with the outwardly facing shoulder 80, and a cylinder closure or head 1 117 is disposed within the outer land S4'inengagement with the outwardly facing shoulder 81. Interposed between the separator 116 and cylinder closure or head 117 is a filter disc 118; and, a dead soft seal ring 119 is wedged between the land 84, shoulder 81 and cylinder head 117, the latter being positively retained in positionwithin thecylinder by a resilient C-shaped retaining ring 126. Provided on the cylinder head 117 is a discharge shut-off valve 121 which communicates through the cylinder head 117, filter disc 118, separator 116 and high pressure discharge valve 111 with the Working interior of the cylinder 29. Outlet connection means 122 are provided. on the discharge shut-off valve 121, as for connection to a refrigerating coil, pneumatically operated device, etc.. While the inlet and discharge shut-off valves 108 and 122, respectively, may be manually operated, if desired, the low pressure inlet valve 96 and high pressure dischargevalve 111 are necessarily completely automatic, opening: and closing in response to predetermined pressure differentials, and may be of the well-known, spring-pressed flutter type valves.

Disposed within the open rear of the compressor housing 21 is a generally circular, rearwardly cuppedl wall 124 having its peripheral :marginal portion 125 seated against the rearwardly facing, annular shoulder 39 and maintained thereagainst -by a resilient, c-shaped retaining ring 126 received inthe annular groove 41. One or more locating pins 127 are used to properlyposie ment with the retaining ring 160.

128, preferably of dead soft aluminum or othersuitable material is wedged between the wall 124 and the-shoulder 39 to seal the juncture thereof. The wall-124 is formed centrally with an open-ended, tubular journal support 130, and on its forwardface with a plurality of fins, blades or webs 131 extending radially from the'journal support. The journal support is arranged coaxially with the journal support 43, and has an enlarged rearward portion 132 formed with a diagonal through bore 133, communicating between the upper cupped or hollow part of the wall 124 and the interior'of the enlarged rearward journal support portion 132.

A pair of similar, tubular bearings 135'and 136fare seated in the journal bearing supports 43 and 1311,16- spectively, each of the bearings being formed with an upstanding, segmental flange or wall, as at 137 and 138. The flange 137 combines with the upper ribs, fins or webs 44 of the front housing wall 31 and the upperportionof the journal support 43 to define a well for containing liquid lubricant, while the flange or wall 135 combines 'with the upper fins, ribs or webs 131 and the upper portion of the journal support 130 to form another Well for holding liquid lubricant.

A drive shaft 140 extends transversely through the piston unit 92, being operatively connected to the latter for effectingreciprocation thereof as will be seen in greater detail hereinafter, and is rotatably supported in the bearings 135 and 136. Further, the shaft 140 extends rearwards through and beyond the journal support 1319 for connection to a suitable driving means. An appropriate shaft seal 142 is circumposed about the shaft 141? in the rearward, enlarged portion'1'32 of the journal support 139; and, a shaft seal seat 143 is retained in the enlarged tubular portion 132 by a C-shaped retaining ring 144. It'will now'be appreciatedthat the wall 124 combines with the compressor housing section 21 to completely enclose the space within the'latter-and define a hermetically sealed casing or chamber.

The auxiliary housing section or motor shell 22 is generally cylindrical in configuration and disposed just rearwards of the compressor housing section. More specifically, the motor shell 22 has its front end open and detachably secured to the rear end of the compressor housing section by bolts or other suitable securing means. Locating pins 146'are employed to properly'position the motor shell with respect to the compressor housing, and a seal ring 147 serves to hermetically seal the motor shell. The rear end of the motor shell 22 is closed by an end wall 148, and a suitable opening (not shown) is provided for electric Wires entering the shell. External ribs or fins 149 are advantageously provided on the auxiliary housing 22 including the rear end wall 148, for dissipating heat generated within the auxiliary housing or shell.

The rearwardly extending portion of the shaft 140, as at 151, is disposed longitudinally within the auxiliary shell 22, and terminates in a reduced end 'port'ion152 adjacent to the rear auxiliary shell end wall 148. A shaftless motor is the preferred form of drive means, and is illustrated as including an outer stator 154 seated within the auxiliary shell 22 and fixedly positioned therein by one or more set screws 155. Keyed to the rearwardly extending shaft portion 151, as at 158, is an inner rotor 157 which effects rotary movement of the shaft. A retaining ring 161) is circumposed about the shaft portion 151 just forwardly of the rotor 157, and a hub 161 is longitudinally slidable on the reduced shaft end portion 152 and resiliently biased forwardly by a coil spring 162 against the motor rotor to maintain the latter in engage- If desired, fan blades 1363 maybe provided onthe hub 161 for cooling the mbton'however, this has been found to be unnecessary under most operating conditions.

The double piston unit As best seen in Fig. 19, the double or dumbbell-like piston unit 92 includes a hollow, relatively large, low pressure piston 164, a hollow, relatively small high pressure piston 159, in longitudinal alignment with the low pressure piston and connected to the latter by a plurality of parallel spaced, rectangularly arranged hollow struts 165 (four being illustrated in the drawings see Fig. 6). That is, the struts 165 are generally tubular in construction preferably with walls of minimum thickness, and each opens at its opposite ends into the interiors of the low pressure and high pressure pistons 164 and 159, respectively.

The interior of the low pressure piston 164 is formed with an annular, longitudinally outwardly facing shoulder 166 and an annular internal groove 167, the latter being spaced between the shoulder and the outer end of the low pressure piston. A valve back-up member 163 is disposed within the low pressure piston 164 in engagement with the annular shoulder 166. A low pressure discharge valve 169 and a low pressure discharge valve seat 170 are also disposed within the low pressure cylinder, the discharge valve being located between the back-up member and valve seat, and all being held in the low pressure piston by a C-shaped retaining ring 171 received in the groove 167. A dead soft seal ring 172 is wedged between the valve seat 1711 and the interior surface of the piston 164 to prevent the passage of fluid therebetween; and, a plurality of piston rings 173 are circumposed about the exterior of the low pressure piston.

The hollow interior of the high pressure piston 159 is also formed with an annular, outwardly facing shoulder 176 substantially spaced from the outer piston end, and an annular, internal groove 177 adjacent to the outer piston end. A high pressure inlet valve 178 is positioned interiorly of the high pressure piston 159, interposed between a high pressure inlet valve seat 179 and a high pressure inlet valve back-up member 1811. The high pressure inlet valve seat 179 is disposed in engagement with the internal shoulder 176, and the valve seat, valve and back-up member are held in position by a C-shaped retaining ring 181 located in the groove 177 and engaging the back-up member. A dead soft seal ring 182 is wedged between the high pressure inlet valve seat 179 and the interior surface of the high pressure piston to prevent the passage of fluid therebetween, and a plurality of piston rings 183 are circumposed about the high pressure piston in the conventional manner.

The rectangularly arranged tubular struts 165 are substantially spaced apart to define intersecting vertical and horizontal passageways therebetween. The horizontal passageway is partially closed by a web 185 extending between each adjacent pair of vertically spaced struts. The webs 185 are apertured in alignment with each other, as at 186 and each provided with a journal hearing or bushing 187. A connecting rod 188 (see Fig. 2) is disposed in the vertical passageway defined between horizontally spaced pairs of struts 165 and has a wrist pin 189 extending transversely through one end and journaled in the bearings 187. Stated otherwise, the connecting rod 188 is pivotally connected to the double piston unit 92. by the wrist pin 139. The wrist pin 189 is non-rotatably secured to the connecting rod 188 by the pin 199 extending through the connecting rod and wrist pin at right angles to the latter, so that all relative rotation takes place between the wrist pin and bearings 187. Lubricating passageways, as at 191, are advantageously formed in the wrist pin 189 communicating between the interior of the latter and the bearing surfaces thereof. Additional lubricating passageways are provided by grooves 192 formed on opposite sides of the connecting rod for lubricating relative movement between the latter and the struts.

The crank end 193 of the connecting rod 188 is disposed in the vertical, inter strut passageway adjacent to the high pressure piston 159 and provided internally with a rotary eccentric 194. The drive shaft 149 extends through the horizontal inter strut passageway and through the eccentric 194, eccentrically thereof, and is keyed to the eccentric for effecting positive rotation of the latter about the axis of the shaft. Thus, rotation of the shaft will oscillate the connecting rod 188 and reciprocate the pistons 164 and 159, in the cylinders 28 and 29, respectively. A pair of lubricating passageways 195 extend into the connecting rod 138 and communicate with the sliding surfaces of the connecting rod and eccentric to lubricate the latter. Toward this end, curved lips or tongues 196 project from the connecting rod adjacent to the passageways 195, to collect liquid lubricant and guide the latter toward the passageways.

The lubricating system Keyed to the shaft 140 on opposite sides of the struts are a pair of counterweights 199, (Figs. 14-18), which are preferably identical in construction for simplicity of assembly (see Fig. 16), and are proportioned to completely balance all vertical vibrational forces. Each counterweight comprises an oblong plate of generally segmental configuration, having a through bore 2% adjacent to one end formed with one or more keyways, and a plurality of arcuate grooves or recesses 201 extending inwards from the other plate end. That is, each face of the counterweight plate is formed with a plurality of arcuate, substantially parallel grooves or recesses extending inwards from the plate end remote from the bore 290. In addition, one face of each counterweight plate is formed with a plurality of arcuate pockets or recesses 202 arranged in equally spaced relation circumferentially about the bore 290. Upon rotation of the shaft 140, and hence of the counterweights 199, the grooved ends of the counterweights will engage in a pool of oil or other liquid lubricant contained in the lower region of the compressor housing, so as to receive and hold lubricant in the grooves 2531 for centrifugal discharge upwards against the top housing wall 33 upon continued rotation of the counter weights. The counterweights are arranged to rotate in the direction of the arrow (Fig. 2), so that liquid is forced onto the grooves 201 through the open ends thereof. The liquid thrown centrifugally against the top housing wall will drip down, primarily from the rib 34 to effectively lubricate the connecting rod, wrist pin and eccentric. In addition, the counterweights effect substantial splashing of liquid from the pool or reservoir into the wells defined on the journal supports 43 and 130, and to the piston bearing surfaces. As a continuous supply of lubricant is afforded the wells formed on the journal supports, there will be constant flow of lubricant downwards through the bores 49 and 133 and thence into the journal bearings 135 and 136.

The.dispersoid separator 116 is best seen in Figs. 7-11, and includes a generally vertically disposed cylindrical or circular partition wall barrier or body 204 interposed in the high pressure cylinder 29 and extending thereacross between the piston 94 and the cylinder head or outer closure 117, and more specifically between the high pressure discharge valve 111 and the discharge filter 118. The body or wall 204 is formed in its upper portion with a groove 295 for receiving a vertically disposed locating pin 206, and is formed in its lower region with a notch 2117 opening into the bore or passageway 89. On the outer side of the cylindrical body or wall 2%, adjacent to the cylinder head 117, is provided a projection 208 having a pair of vertically disposed cylindrical cavities 299 formed therein. The outwardly projecting separator body portion 298 has its upper end 210 spaced from the upper region of the cylinder 29, or more specifically, from the adjacent portion of the internal land 83, and has its lower end 211 disposed in conforming engage assess? ment with the adjacent 'siirfa ce 6f the land 83. The cylindrical cavities 209 open through the lower end of the projecting body portion 208 and are preferably longitudinally grooved or internally fluted, as at 212 throughout substantially their entire length. In addition, the body portion 208 intermediate the open lower ends of the cavities 209 is recessed upwards, as at 213, which recess communicates through the groove or notch 207 with the passageway 89.

The upper end of each cylindrical cavity 209 is closed except for a vertically dispose-d tube 214 which depends spacedly within each cavity terminating at its lower end above the adjacent portion of the land 83 and opening through the upper end of the body projection 208 into the cylinder 29. A pair of ports 215 are formed in the wall or barrier 204 and each opens into one of the cylindrical cavities 209 adjacent to the upper end thereof and substantially tangential thereto. The projecting body portion 208 may be provided with laterally extending chordal segments 216 to insure accurate positioning of the partition wall or barrier 204 in the cylinder 29 and prevent Wobbling or other displacement of the separator under high fluid pressures.

During compressor operation, the finally compressed fluid from the high pressure discharge valve 111 will pass through the ports 215 and thus tangentially enter the annular spaces defined between the surfaces of the cavities 209 and the tubes 214. Relatively heavy particles or dispersoid contained in the compressed fluid will be centrifugally forced into the grooves 212, so as to impinge the surfaces thereof and be captured therein. The thus captured dispersoid will flow downwards along the grooves to the bottom of the cavities 209, and thence through the recess 213 and notch 207 into the passageway 89. In addition to a swirling movement in the cavities 209, the fluid passes downwards exteriorly of the tubes 214 and thence upwards through the tubes into the space outwardly of the wall 204. Along this vertically reversed path of fluid movement, the relatively heavy particles or dispersoid not captured in the grooves 212 will fall to the lower ends of the cavities 209 and also pass through the recess 213 and notch 207 into the passageway 89.

As mentioned hereinbefore, the passageway 89 communicates through the external boss 64 and the passageway or port 90 with the cylindrical interior 47 of the pocket or body 46.

Disposed within the pocket 46 is a generally cylindrical, previous tube 217 containing a suitable agent for cleaning the separated dispersoid, such as silica gel or other purifying and dehydrating substance. The tube 217 is closed at its ends by porous plugs 218 permitting the passage therethrough of the separated dispersoid, the plugs being maintained in position by closure heads 219, which are in turn maintained in position by C-shaped retaining rings 220. Seal rings 221 are preferably wedged between the closure heads 219 and the adjacent internal surfaces of the pockets 46 to prevent escape of separated dispersoid around the closure heads. As the separated dispersoid is under substantial pressure from the finally compressed fluid, it will pass readily through the filtering plugs 218, any heavy residue being collected in the trough 48, and after purification and dehydration by the silica gel, will be forced through the porous tube 217 into the passage 53 and bore 52. Hence, a constant supply of clean lubricant will be readily available at the valve 55 of the bore 52.

Upon rotation of the shaft 140 and the counterweights or splashers 199, the counterweight adjacent to the valve 55 will effect opening and closing of the latter in predetermined timed relation with respect to the compressor peration. More specifically, the valve 54 will periodically communicate through its apertured head with the recesses or grooves 202 (see Fig. 14) to open the bore 52 and permit the passage of clean lubricant into the latter grooves. Each of the grooves 202 moves successively from the 10 region of the valve 54 to'the region of thepin 59, the latter entering into each groove,as seen in Fig. 15, to Wipe the latter clean and discharge all lubricating liquid therefrom into the interior-of the compressor housing. In this manner, there is fed a predetermined quantity of filtered lubricant back into the liquid pool, dependent upon the speed of compressor operation.

Compressor operation Upon energization of the motor, the rotor 157 will effect-rotation of the shaft to rotate the counterweights 199 and reciprocate the double piston unit 92. As the piston unit reciprocates from right to left (see Fig. 2), the low pressure inlet valve will be opened, while the low pressure discharge valve is closed, to draw fluid into the low pressure cylinder. Reciprocation to the right will effect closing of the low pressure inlet valve and compression of the fluid contained in the low pressure cylinder until a predetermined value of pressure is reached, when the low pressure discharge valve will open to permit the escape of partially compressed fluid into the tubular struts 165. Similarly, upon reciprocation of the double piston unit 92 toward the right, as seen in Fig. 2, the high pressure inlet valve will be opened by the fluid under pressure in the tubular struts to permit the ingress of partially compressed fluid into the high pressure cylinder 29; and, upon reciprocation of the piston unit to the left, the high pressure inlet valve will be closed and the fluid compressed in the high pressure cylinder until a predetermined value of pressure is reached. At this time the high pressure discharge valve opens to permit the discharge of finally compressed fluid for passage through the dispersoid separator 116 and thence out through the high pressure shut-off valve 12. Of course, the finally compressed fluid is thoroughly cleaned, all particles and dispersoid having been removed during passage through the separat'or 116,

In order to effect considerable increase in efliciency, the splasher-counterweights 199 discharge liquid lubricant centrifugally from the grooves 201 against the top wall 33 of the compressor housing, as described hereinbefore.

The upwardly discharged liquid lubricant is cooled by contact with the finned high conductivity wall 33 and cascades downwards therefrom over the relatively thin walled, tubular struts to remove heat therefrom. Thus, in addition to eliminating cumbersome and inefficient interstage conduits, the tubular struts provide a direct interstage conduit means which permits of effectively cooling the partially compressed fluid to obtain greater work from the high pressure cylinder and increased total compressor efliciency.

From the foregoing, it is seen that the present invention provides a compressor which fully accomplishes its intended objects, which is well adapted to meet practical conditions of manufacture, maintenance and use.

Although the present invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is understood that certain changes and modifications may be made within the spirit of the invention and scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. In a compressor including a generally horizontal cylinder having one end closed, and a piston slidable in said cylinder toward and away from said closed end, the

improvement comprising a body interposed in said cylinder between said closed end and said piston to subdivide said cylinder into inner and outer chambers adjacent to said piston and closed end, respectively, there being a generally vertically disposed cylindrical cavity formed in said body and opening adjacent its upper end into said inner chamber for receiving compressed fluid from the latter, and a tube disposed in spaced relation within said cavity having its lower end opening into said cavity adjacent to the lower end of the latter and having its upper 11 end opening through said body into said outer chamber, whereby relatively heavy dispersoid in said fluid will fall by gravity to the lower end of said cavity and relatively clean fluid will pass outwards through said tube.

2. A device according to claim 1, wherein the opening between said inner chamber and cavity is disposed generally tangential with respect to the latter for efiecting a swirling fluid movement in said cavity, whereby additional dispersoid will be centrifugally separated from said fluid and captured by said grooves.

References Cited in the file of this patent UNITED STATES PATENTS Deschamps Oct. 26, 1915 Nevitt Apr. 17, 1923 Brockway Oct. 1, 1929 Lombard Nov. 28, 1933 Borgerd Mar. 23, 1937 Teeter May 28, 1940 Maniscalco July 9, 1946 Thompson Nov. 2, 1948 Mayer et al Dec. 11, 1951 

